The equation of motion for viscous-damped free vibrations is $$m\frac{d^2x}{dt} + c\frac{dx}{dt} + kx=0$$ What does each term represent?

A. Term 1: acceleration force, Term 2: equilibrium force, Term 3: spring damping force
B. Term 1: acceleration force, Term 2: coriolis force, Term 3: spring force
C. Term 1: acceleration force, Term 2: damping force, Term 3: spring force
D. Term 1: gravitational force, Term 2: damping force, Term 3: spring damping force
E. Term 1: gravitational force, Term 2: friction force, Term 3: spring force